The prospect of diminishing supplies of fossil fuel has prompted the development of means for utilizing solar energy collectors and heat pumps and heat storage reservoirs in system combinations that evoked little interest in the past. The development of the apparatus to build systems has been slow notwithstanding the fact that a very great body of the required technical information is available. There are sensing techniques and microprocessors and servo technology with which to design a wide range of energy efficient heating and cooling systems, but there is a lack of "building blocks" with which to turn designs into operating systems.
A major problem has been the fact that systems must be customized. The combined solar and gas fired heating system for a home on the east side of the street that has no swimming pool must be substantially different from that of the home that has a heat and cold storage reservoir in the form of a swimming pool, or which is located on the west side of the street where a solar collector can take greater advantage of afternoon sunshine.
The lack of system uniformity has been a problem for manufacturers of systems components. The result is that components are expensive, and components that will interfit properly to create a system are sometimes difficult to find. Valves are among the components that have been difficult. In general, systems that combine solar and gas or oil fired heating must operate at very low pressure. Adequate flow rates are achieved only with fairly large diameter flow conduits and large values. There are few large capacity, chemically inert, corrosion resistant, low pressure loss valves for controlling fluid flow. The cost of large brass valves destroys the cost effectiveness of systems of even modest complexity. What has been needed are non-restrictive flow control valves of large capacity which are capable of low cost manufacture without sacrifice of the qualities that ensure the years of trouble-free service that must be achieved in practical systems.
Energy transfer is not the only field in which there is a pressing need for improved valves and for stackable valves, in particular. The chemical processing industries, the food and beverage processing industries, the farming industries, the electroplating industries, and many others, have a need for improved low cost valves, especially high capacity and low pressure valves.